Hardmask composition and method of forming pattern by using the hardmask composition

ABSTRACT

A hardmask composition may include a solvent and a 2-dimensional carbon nanostructure containing about 0.01 atom % to about 40 atom % of oxygen or a 2-dimensional carbon nanostructure precursor thereof. A content of oxygen in the 2-dimensional carbon nanostructure precursor may be lower than about 0.01 atom % or greater than about 40 atom %. The hardmask composition may be used to form a fine pattern.

RELATED APPLICATION

This application is a divisional of U.S. application Ser. No.14/725,390, filed on May 29, 2015, which claims priority under 35 U.S.C.§119 to Korean Patent Application Nos. 10-2014-0066524, filed on May 30,2014, and 10-2014-0114530, filed on Aug. 29, 2014, in the KoreanIntellectual Property Office. The entire contents of each of theabove-referenced applications are hereby incorporated by reference.

BACKGROUND

1. Field

The present disclosure relates to a hardmask composition, a method ofmanufacturing a hardmask composition, and/or a method of forming apattern by using the hardmask composition.

2. Description of Related Art

The semiconductor industry has developed ultra-fine techniques forproviding a pattern of several to several tens of nanometer size, whichmay benefit from effective lithographic techniques. A typicallithographic technique includes providing a material layer on asemiconductor substrate, coating a photoresist layer on the materiallayer, exposing and developing the same to provide a photoresistpattern, and etching the material layer by using the photoresist patternas a mask.

As the size of the pattern to be formed becomes smaller, it may bedifficult to provide a fine pattern having a desirable profile by onlythe typical lithographic technique described above. Accordingly, alayer, called “a hardmask”, may be formed between the material layer forthe etching and the photoresist layer to provide a fine pattern. Thehardmask serves as an interlayer that transfers the fine pattern of thephotoresist to the material layer through a selective etching process.Thus, it is desirable for the hardmask layer to have chemicalresistance, thermal resistance, and etching resistance in order totolerate various types of etching processes.

As semiconductor devices have become highly integrated, a height of amaterial layer has been maintained about the same or has relativelyincreased, although a line-width of the material layer has graduallynarrowed. Thus, an aspect ratio of the material layer has increased.Since an etching process needs to be performed under such conditions,the heights of a photoresist layer and a hardmask pattern also need tobe increased. However, increasing the heights of a photoresist layer anda hardmask pattern is limited. In addition, the hardmask pattern may bedamaged during the etching process for obtaining a material layer with anarrow line-width, and thus electrical characteristics of devices maydeteriorate.

In this regard, methods have been suggested to use a single layer ormultiple layers, in which a plurality of layers are stacked, of aconductive or insulating material such as a polysilicon layer, atungsten layer, and a nitride layer. However, the single layer or themultiple layers requires a high deposition temperature, and thusphysical properties of the material layer may be modified. Therefore, anovel hardmask material is desired.

SUMMARY

Example embodiments relate to a hardmask composition with improvedetching resistance.

Example embodiments relate also to a method of manufacturing a hardmaskcomposition with improved etching resistance.

Example embodiments also relate a method of forming a pattern by usingthe hardmask composition.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of example embodiments.

According to example embodiments, a hardmask composition includes a2-dimensional carbon nanostructure containing about 0.01 atom % to about40 atom % of oxygen or a 2-dimensional carbon nanostructure precursorthereof; and a solvent.

In example embodiments, a content of the oxygen in the 2-dimensionalcarbon nanostructure precursor may be lower than about 0.01 atom % andgreater than or equal to about 0 atom %), or a content of the oxygen inthe 2-dimensional carbon nanostructure precursor may be greater thanabout 40 atom %) and less than or equal to about 80 atom %.

In example embodiments, the 2-dimensional carbon nanostructure precursormay be one of expanded graphite obtained from exfoliated graphite and anoxidation product of acid-treated graphite.

In example embodiments, an intensity ratio of a D mode peak to a G modepeak obtained by Raman spectroscopy of the 2-dimensional carbonnanostructure may be 2 or lower (e.g., in a range of about 0.001 toabout 2).

In example embodiments, an intensity ratio of a 2D mode peak to a G modepeak obtained by Raman spectroscopy of the 2-dimensional carbonnanostructure may be 0.01 or higher (e.g., in a range of about 0.01 toabout 1.0).

In example embodiments, an intensity ratio of a D mode peak to a G modepeak obtained by Raman spectroscopy of the 2-dimensional carbonnanostructure precursor may be in a range of about 0.001 to about 2.

In example embodiments, an intensity ratio of a 2D mode peak to a G modepeak obtained by Raman spectroscopy of the 2-dimensional carbonnanostructure may be in a range of about 0.01 or higher.

In example embodiments, a diffraction angle 2θ of a (002) crystal facepeak obtained by X-ray diffraction analysis of the 2-dimensional carbonnanostructure may be observed within a range of about 20° to about 27°.

In example embodiments, a d-spacing of the 2-dimensional carbonnanostructure obtained by X-ray diffraction analysis may be about 0.3 toabout 0.5 nm.

In example embodiments, the 2-dimensional carbon nanostructure may havecrystallinity in a C-axis, and an average particle diameter of crystalsmay be in a range from about 1 nm to about 100 nm.

In example embodiments, the solvent may include at least one of water,methanol, isopropanol, ethanol, N,N-dimethylformamide,N-methylpyrrolidone, dichloroethane, dichlorobenzene,N,N-dimethylsulfoxide, xylene, aniline, propylene glycol, propyleneglycol diacetate, methoxy propanediol, diethylene glycol, gammabutyrolactone, acetyl acetone, cyclohexanone, propylene glycolmonomethyl ether acetate, γ-butyrolactone, O-dichlorobenzene,nitromethane, tetrahydrofuran, dimethyl sulfoxide, nitrobenzene, butylnitrite, methyl cellosolve, ethyl cellosolve, diethyl ether, diethyleneglycol methyl ether, diethylene glycol ethyl ether, dipropylene glycolmethyl ether, toluene, hexane, methyl ethyl ketone, methyl isobutylketone, hydroxymethyl cellulose, and heptane.

In example embodiments, a fraction of sp² carbon may be equal to or amultiple of a faction of sp³ carbon in the 2-dimensional carbonnanostructure.

In example embodiments, the 2-dimensional carbon nanostructure may beincluded in the hardmask composition.

In example embodiments, a sp² carbon fraction may be greater than a sp³carbon fraction in the 2-dimensional carbon nanostructure.

In example embodiments, an intensity ratio (I_(D)/I_(G)) of a D modepeak to a G mode peak obtained by Raman spectroscopy of the2-dimensional carbon nanostructure may be in a range from about 0.001 toabout 2.0, and an intensity ratio (1_(2D)/I_(G)) of a 2D mode peak to aG mode peak obtained by Raman spectroscopy of the 2-dimensional carbonnanostructure may be in a range from about 0.01 to about 1.0.

In example embodiments, a d-spacing obtained from X-ray diffractionanalysis of the 2-dimensional carbon nanostructure may be in a rangefrom about 0.3 to about 0.7 nm.

In example embodiments, the 2-dimensional carbon nanostructure may havecrystallinity in a C-axis. An average particle diameter of the crystalsmay be in a range of about 1.0 Å to about 1000 Å.

According to example embodiments, a method of forming a pattern includesforming a to-be-etched layer on a substrate; forming a hardmask on theto-be-etched layer by supplying the hardmask composition including a2-dimensional carbon nanostructure containing about 0.01 atom % to about40 atom % of oxygen; forming a photoresist pattern on the hardmask;forming a hardmask pattern on the to-be-etched layer by etching the2-dimensional carbon nanostructure by using the photoresist pattern asan etching mask, the hardmask pattern including the 2-dimensional carbonnanostructure; and etching the to-be-etched layer by using the hardmaskpattern as an etching mask.

In example embodiments, the forming the hardmask on the to-be-etchedlayer may include coating the hardmask composition on the to-be-etchedlayer.

In example embodiments, the method may further include heat-treating thehardmask composition, wherein the heat-treatment may be performed duringor after the coating the hardmask composition on the to-be-etched layer.

In example embodiments, the forming the hardmask on the to-be-etchedlayer may include one of: coating the 2-dimensional carbon nanostructureprecursor on the to-be-etched layer and then oxidizing or reducing thecoated 2-dimensional carbon nanostructure precursor; oxidizing orreducing the 2-dimensional carbon nanostructure precursor into the2-dimensional carbon nanostructure and then coating the 2-dimensionalcarbon nanostructure on the to-be-etched layer; and simultaneouslycoating and oxidizing or reducing the 2-dimensional carbon nanostructureprecursor on the to-be-etched layer.

In example embodiments, the reducing may be performed by chemicalreduction, heat-treatment reduction, or electrochemical reduction.

In example embodiments, the chemical reduction may be performed using atleast one reducing agent. The at least one reducing agent may includeone of ammonia-borane, hydrazine, sodium borohydride, dimethylhydrazine,sulfuric acid, hydrochloric acid, hydrogen iodide, hydrogen bromide,hydrogen sulfide, hydroquinone, hydrogen, and acetic acid.

In example embodiments, the heat-treatment may be performed at atemperature of about 100° C. to 1500° C.

In example embodiments, the oxidizing may be performed using at leastone of an acid, an oxidizing agent, UV, ozone, IR, heat-treatment, andplasma.

In example embodiments, the 2-dimensional carbon nanostructure of thehardmask pattern may be a structure formed by stacking 2-dimensionalnanocrystalline carbon layers.

In example embodiments, a thickness of the hardmask may be about 10 nmto about 10,000 nm.

In example embodiments, the step of forming the hardmask on theto-be-etched layer may be performed using at least one of spin coating,air spray, electrospray, dip coating, spray coating, a doctor blademethod, and bar coating.

According to example embodiments, a method of making a hardmaskcomposition includes preparing a 2-dimensional carbon nanostructureprecursor; and forming a 2-dimensional carbon nanostructure by adjustingan oxygen content of the 2-dimensional carbon nanostructure precursorsuch that the 2-dimensional carbon nanostructure contains about 0.01atom % to about 40 atom % of oxygen. A content of the oxygen in the2-dimensional carbon nanostructure precursor may be lower than about0.01 atom % and greater than or equal to about 0 atom %. Alternatively,a content of the oxygen in the 2-dimensional carbon nanostructureprecursor may be greater than about 40 atom % and less than or equal toabout 80 atom %.

In example embodiments, the preparing the 2-dimensional carbonnanostructure precursor may include exfoliating graphite.

In example embodiments, the preparing the 2-dimensional carbonnanostructure precursor may include heat-treating the 2-dimensionalcarbon nanostructure precursor.

In example embodiments, the forming the 2-dimensional carbonnanostructure may include at least one of oxidizing the 2-dimensionalcarbon nanostructure precursor and reducing the 2-dimensional carbonnanostructure precursor.

In example embodiments, the oxidizing the 2-dimensional carbonnanostructure precursor may include using at least one of an acid, anoxidizing agent, UV, ozone, IR, a heat-treatment process, and a plasmaprocess.

In example embodiments, the reducing the 2-dimensional carbonnanostructure precursor may include at least one of chemical reduction,heat-treatment reduction, and electrochemical reduction.

In example embodiments, a method of forming a hardmask may includecoating a solvent and the 2-dimensional carbon nanostructure precursoron a substrate, forming the 2-dimensional carbon nanostructure during orafter the coating the solvent and the 2-dimensional carbon nanostructureprecursor; baking the solvent and the 2-dimensional carbon nanostructureon the substrate after the forming the 2-dimensional carbonnanostructure; and performing a heat-treatment process on the2-dimensional carbon nanostructure after the baking the solvent and the2-dimensional carbon nanostructure.

In example embodiments, a method of forming a hardmask may includecoating a solvent and the 2-dimensional carbon nanostructure on asubstrate; baking the solvent and the 2-dimensional carbon nanostructureon the substrate; and performing a heat-treatment process on the2-dimensional carbon nanostructure after the baking the solvent and the2-dimensional carbon nanostructure.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of non-limiting embodiments,as illustrated in the accompanying drawings in which like referencecharacters refer to like parts throughout the different views. Thedrawings are not necessarily to scale, emphasis instead being placedupon illustrating principles of inventive concepts. In the drawings:

FIG. 1 illustrates a method of preparing a hardmask composition on ato-be-etched layer according to example embodiments;

FIG. 2 illustrates a method of preparing a hardmask composition on ato-be-etched layer according to example embodiments;

FIG. 3 illustrates a method of preparing a hardmask composition on ato-be-etched layer according to example embodiments;

FIG. 4 illustrates a method of preparing a hardmask composition on ato-be-etched layer according to example embodiments;

FIGS. 5A to 5E illustrate a method of forming a pattern by using ahardmask composition according to example embodiments;

FIG. 5F illustrates a part of method of forming a pattern by using ahardmask composition according to example embodiments.

FIGS. 6A to 6D illustrate a method of forming a pattern by using ahardmask composition according to example embodiments;

FIGS. 7A to 7D illustrate a method of forming a pattern by using ahardmask composition according to example embodiments;

FIGS. 8A to 8D illustrate a method of forming a pattern by using ahardmask composition according to example embodiments;

FIG. 9 is X-ray diffraction analysis results of 2-dimensional carbonnanostructures prepared in Examples 1 to 3 and an amorphous carbonprepared in Comparative Example 1; and

FIG. 10 is Raman spectroscopy analysis results of the 2-dimensionalcarbon nanostructures prepared in Examples 1 to 3, high-temperatureamorphous carbon prepared in Comparative Example 1, and low-temperatureamorphous carbon prepared in Comparative Example 2.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings, in which some example embodiments are shown.Example embodiments, may, however, be embodied in many different formsand should not be construed as being limited to the embodiments setforth herein; rather, these example embodiments are provided so thatthis disclosure will be thorough and complete, and will fully convey thescope of example embodiments of inventive concepts to those of ordinaryskill in the art. In the drawings, the thicknesses of layers and regionsare exaggerated for clarity. Like reference characters and/or numeralsin the drawings denote like elements, and thus their description may beomitted.

It will be understood that when an element is referred to as being“connected” or “coupled” to another element, it can be directlyconnected or coupled to the other element or intervening elements may bepresent. In contrast, when an element is referred to as being “directlyconnected” or “directly coupled” to another element, there are nointervening elements present. Other words used to describe therelationship between elements or layers should be interpreted in a likefashion (e.g., “between” versus “directly between,” “adjacent” versus“directly adjacent,” “on” versus “directly on”). As used herein, theterm “and/or” includes any and all combinations of one or more of theassociated listed items.

It will be understood that, although the terms “first”, “second”, etc.may be used herein to describe various elements, components, regions,layers and/or sections. These elements, components, regions, layersand/or sections should not be limited by these terms. These terms areonly used to distinguish one element, component, region, layer orsection from another element, component, region, layer or section. Thus,a first element, component, region, layer or section discussed belowcould be termed a second element, component, region, layer or sectionwithout departing from the teachings of example embodiments.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of exampleembodiments. As used herein, the singular forms “a,” “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“comprises”, “comprising”, “includes” and/or “including,” if usedherein, specify the presence of stated features, integers, steps,operations, elements and/or components, but do not preclude the presenceor addition of one or more other features, integers, steps, operations,elements, components and/or groups thereof. Expressions such as “atleast one of,” when preceding a list of elements, modify the entire listof elements and do not modify the individual elements of the list.

Example embodiments are described herein with reference tocross-sectional illustrations that are schematic illustrations ofidealized embodiments (and intermediate structures) of exampleembodiments. As such, variations from the shapes of the illustrations asa result, for example, of manufacturing techniques and/or tolerances,are to be expected. Thus, example embodiments should not be construed aslimited to the particular shapes of regions illustrated herein but areto include deviations in shapes that result, for example, frommanufacturing. Thus, the regions illustrated in the figures areschematic in nature and their shapes are not intended to limit the scopeof example embodiments.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which example embodiments belong. Itwill be further understood that terms, such as those defined incommonly-used dictionaries, should be interpreted as having a meaningthat is consistent with their meaning in the context of the relevant artand will not be interpreted in an idealized or overly formal senseunless expressly so defined herein.

Hereinafter, hardmask compositions according to example embodiments andmethods of forming a pattern by using the hardmask compositions will bedescribed in detail.

According to example embodiments, a hardmask composition includes a2-dimensional carbon nanostructure containing about 0.01 atom % to about40 atom % of oxygen or a 2-dimensional carbon nanostructure precursor;and a solvent.

As used herein, the term “2-dimensional carbon nanostructure” refers toa sheet structure of a single atomic layer formed by a carbon structurethat forms polycyclic aromatic molecules in which a plurality of carbonatoms are covalently bound to one another and aligned into a planarshape, a network structure in which a plurality of carbon structureseach having a plate shape as a small film piece are interconnected andaligned into a planar shape, or a combination thereof. The covalentlybound carbon atoms form repeating units that comprise 6-membered ringsbut may also form 5-membered rings and/or 7-membered rings. The carbonstructure may be formed by stacking a plurality of layers includingseveral sheet structures and/or network structures, and an averagethickness of the carbon structure may be about 100 nm or less, forexample, about 10 nm or less, or in a range of about 0.01 nm to about 10nm. A thickness of the carbon structure may be in a range of about 0.01nm to about 100 nm.

The 2-dimensional carbon nanostructure according to example embodimentsmay include oxygen atoms in addition to carbon atoms rather than being acomplete C═C/C—C conjugated structure. Also, the 2-dimensional carbonnanostructure may have a carboxyl group, a hydroxy group, an epoxygroup, or a carbonyl group at its end.

An oxygen content of the 2-dimensional carbon nanostructure may be, forexample, in a range of about 6.5 atom % to about 19.9 atom %, forexample, about 10.33 atom % to about 14.28 atom %. In the 2-dimensionalcarbon nanostructure, the oxygen content may be confirmed by, forexample, an XPS analysis.

When an oxygen content is 0.01 atom % or less in the 2-dimensionalcarbon nanostructure, the etching resistance of a hardmask formed byusing a hardmask composition including the 2-dimensional carbonnanostructure may deteriorate, and when an oxygen content is 40 atom %or higher, degassing may occur during an etching process.

In example embodiments, the 2-dimensional carbon nanostructure may havean oxygen content within the ranges described above (.e.g., containingabout 0.01 atom % to about 40 atom % of oxygen, containing about 6.5atom % to about 19.9 atom % of oxygen, and/or containing about 10.33atom % to about 14.28 atom % of oxygen), and thus may have hydrophilicproperty so that a bonding strength to another layer may be improved.Also, a dispersing property of the 2-dimensional carbon nanostructure ina solvent may improve, and thus the hardmask composition may be moreeasily prepared. In addition, due to the high bond-dissociation energyof a functional group including an oxygen atom, etching resistance to anetching gas may improve.

In example embodiments, the 2-dimensional carbon nanostructure may havepeaks observed at about 1340 cm⁻¹ to about 1350 cm⁻¹, about 1580 cm⁻¹,and about 2700 cm⁻¹ in Raman spectrum analysis. The peaks provideinformation related to a thickness, a crystallinity, and a charge dopingstatus of the 2-dimensional carbon nanostructure. The peak observed atabout 1580 cm⁻¹ is a “G mode” peak, which is generated by a vibrationmode corresponding to stretching of a carbon-carbon bond. Energy of the“G mode” is determined by a density of excess charge doped in the2-dimensional carbon nanostructure. Also, the peak observed at about2700 cm⁻¹ is a “2D mode” peak that is useful in the evaluation of athickness of the 2-dimensional carbon nanostructure. The peak observedat about 1340 cm⁻¹ to about 1350 cm⁻¹ was a “D mode” peak, which appearswhen an sp² crystal structure has defects and is mainly observed whenmany defects are found around edges of a sample or in the sample itself.Also, a ratio of a D peak intensity to a G peak intensity (an D/Gintensity ratio) provides information of a degree of disorder ofcrystals of the 2-dimensional carbon nanostructure.

In example embodiments, an intensity ratio (I_(D)/I_(G)) of a D modepeak to a G mode peak obtained from Raman spectroscopy analysis of the2-dimensional carbon nanostructure may be 2 or lower. For example, theintensity ratio (I_(D)/I_(G)) may be within a range of about 0.001 toabout 2.0. An intensity ratio (I_(D)/I_(G)) of a D mode peak to a G modepeak obtained from Raman spectroscopy analysis of the 2-dimensionalcarbon nanostructure precursor may be 2 or lower. For example, inexample embodiments, the intensity ratio (I_(D)/I_(G)) may be within arange of about 0.001 to about 2.0. For example, in example embodiments,the intensity ratio (I_(D)/I_(G)) may be within a range of about 0.001to about 1.0.

In example embodiments, an intensity ratio (1_(2D)/I_(G)) of a 2D modepeak to a G mode peak obtained from Raman spectroscopy analysis of the2-dimensional carbon nanostructure may be 0.01 or higher. For example,the intensity ratio (1_(2D)/I_(G)) may be within a range of about 0.01to about 1.0, or about 0.05 to about 0.5.

In example embodiments, an intensity ratio (1_(2D)/I_(G)) of a 2D modepeak to a G mode peak obtained from Raman spectroscopy analysis of the2-dimensional carbon nanostructure precursor may be 0.01 or higher. Forexample, the intensity ratio (1_(2D)/I_(G)) may be within a range ofabout 0.01 to about 1.0, or about 0.05 to about 0.5.

When the intensity ratio of a D mode peak to a G mode peak and theintensity ratio of a 2D mode peak to a G mode peak are within the rangesabove, the 2-dimensional carbon nanostructure may have a highcrystallinity and a small defect density; consequently, a bonding energyincreases so that a hardmask prepared by using the 2-dimensional carbonnanostructure may have excellent etching resistance.

X-ray diffraction analysis using CuKα is performed on the 2-dimensionalcarbon nanostructure, and as the result of the X-ray analysis, the2-dimensional carbon nanostructure may include a 2-dimensional layeredstructure having a (002) crystal face peak. The (002) crystal face peakmay be observed within a range of about 20° to about 27°.

In example embodiments, a d-spacing of the 2-dimensional carbonnanostructure obtained from the X-ray diffraction analysis may be in therange of about 0.3 to about 0.7, for example, about 0.334 to about0.478. In addition, an average particle diameter of the crystalsobtained from the X-ray diffraction analysis may be about 1 nm orgreater, or for example, in a range of about 23.7 Å to about 43.9 Å.When the d-spacing is within the range, the hardmask composition mayhave excellent etching resistance.

The 2-dimensional carbon nanostructure is formed as a single layer of2-dimensional nanocrystalline carbon or it is formed by stackingmultiple layers of 2-dimensional nanocrystalline carbon.

The 2-dimensional carbon nanostructure according to example embodimentshas a higher content of sp2 carbon than that of sp³ carbon and a highercontent of oxygen compared to a conventional amorphous carbon layer. Ansp² carbon bond (that is, a bond of an aromatic structure) has a higherbonding energy than that of an sp³ carbon bond.

The sp³ structure is a 3-dimensional bonding structure of diamond havinga tetrahedral shape, and the sp² structure is a 2-dimensional bondingstructure of graphite in which a carbon to hydrogen ratio (a C/H ratio)increases and thus may secure resistance to dry etching.

In the 2-dimensional carbon nanostructure, an sp² carbon fraction isequal to or a multiple of an sp³ carbon fraction. For example, an sp²carbon fraction is a multiple of an sp³ carbon fraction by about 1.0 toabout 10, or by about 1.88 to 3.42.

An amount of the sp² carbon atom bonding structure is about 30 atom % ormore, for example, about 39.7 atom % to about 62.5 atom %, in the C1sXPS analysis. Due to the mixing ratio, bond breakage of the2-dimensional carbon nanostructure may be difficult since carbon-carbonbond energy is high. Thus, when a hardmask composition including the2-dimensional carbon nanostructure is used, etching resistancecharacteristics during the etching process may improve. Also, a bondstrength between the hardmask and adjacent layers may increase.

A hardmask obtained by using conventional amorphous carbon mainlyincludes a sp²-centered carbon atom binding structure and thus may haveexcellent etching resistance and low transparency. Therefore, when thehardmasks are aligned, problems may occur, and particles may begenerated during a deposition process, and thus a hardmask manufacturedby using a diamond-like carbon having a sp³-carbon atom bindingstructure has been developed. However, the hardmask has low etchingresistance and thus has a limit in process application.

In example embodiments, a 2-dimensional carbon nanostructure may havegood transparency and excellent etching resistance.

In example embodiments, a 2-dimensional carbon nanostructure may havecrystallinity in a C-axis (a vertical direction of the layer) and anaverage particle diameter of about 1 nm or higher as in the result ofXRD analysis and/or about 1.0 Å or higher as in the result of XRDanalysis. An average particle diameter of the crystals may be, forexample, in a range of about 1.0 Å to about 1000 Å, or about 23.7 Å toabout 43.9 Å. When an average particle diameter of the crystals iswithin this range, the hardmask may have excellent etching resistance.

In hardmask compositions according to example embodiments, any solventcapable of dispersing the 2-dimensional carbon nanostructure or the2-dimensional carbon nanostructure precursor may be used. For example,the solvent may be at least one selected from water, an alcohol-basedsolvent, and an organic solvent.

Examples of the alcohol-based solvent may include methanol, ethanol, andisopropanol, and examples of the organic solvent may includeN,N-dimethylformamide, N-methylpyrrolidone, dichloroethane,dichlorobenzene, dimethylsulfoxide, xylene, aniline, propylene glycol,propylene glycol diacetate, methoxypropanediol, diethyleneglycol,acetylacetone, cyclohexanone, propylene glycol monomethyl ether acetate,γ-butyrolactone, O-dichlorobenzene, nitromethane, tetrahydrofuran,nitromethane, dimethyl sulfoxide, nitrobenzene, butyl nitrite,methylcellosolve, ethylcellosolve, diethylether,diethyleneglycolmethylether, diethyleneglycolethylether,dipropyleneglycolmethylether, toluene, xylene, hexane,methylethylketone, isobutyl ketone, hydroxymethylcellulose, and heptane.

An amount of the solvent may be about 100 parts to about 100,000 partsby weight based on 100 parts by weight of the 2-dimensional carbonnanostructure or the 2-dimensional carbon nanostructure precursor. Whenan amount of the solvent is within this range, the hardmask compositionmay have an appropriate viscosity and thus may easily form a layer.

The 2-dimensional carbon nanostructure precursor may be, for example, i)expanded graphite obtained from exfoliated graphite or ii) an oxidationproduct of acid-treated graphite.

Hereinafter, a method of preparing a hardmask by using a hardmaskcomposition according to example embodiments will be described indetail.

FIG. 1 illustrates a method of preparing a hardmask composition on ato-be-etched layer according to example embodiments.

In example embodiments, the hardmask composition may include a2-dimensional carbon nanostructure containing about 0.01 atom % to about40 atom % of oxygen or a 2-dimensional carbon nanostructure precursorthereof and a solvent.

First, preparation of the hardmask composition including the2-dimensional carbon nanostructure containing about 0.01 atom % to about40 atom % of oxygen will be described.

Referring to FIG. 1, in operation S100, a to-be-etched layer may becoated with the hardmask composition that includes the 2-dimensionalcarbon nanostructure containing about 0.01 atom % to about 40 atom % ofoxygen and a solvent to prepare a hardmask including the 2-dimensionalcarbon nanostructure containing about 0.01 atom % to about 40 atom % ofoxygen.

In operation S110, a heat-treating process may be performed during orafter coating the to-be-etched layer with the hardmask composition.Conditions for the heat-treating process may vary depending on amaterial of the to-be-etched layer, but a temperature of theheat-treating process may be from room temperature (in a range of about20° C. to about 25° C.) to about 1500° C.

The heat-treating process may be performed in an inert gas atmosphereand/or in vacuum.

A heating source of the heat-treating process may be induction heating,radiant heat, lasers, infrared rays, microwaves, plasma, ultravioletrays, or surface plasmon heating.

The inert gas atmosphere may be prepared by mixing a nitrogen gas and/oran argon gas.

After the heat-treating process, in operation S120, the solvent may beremoved. In operation S130, the resultant from which the solvent isremoved may be baked at a temperature of about 100° C. to about 400° C.Then, in operation S140, another heat-treating process may be performedon the baked resultant at a temperature of about 400° C. to about 1,000°C.

When the temperatures of the heat-treating process and the bakingprocess are within these ranges above, hardmasks with excellent etchingresistance may be prepared.

A temperature increasing rate in the heat-treating process and thebaking process may be about 1° C./min to about 1000° C./min. When atemperature increasing rate is within this range, the deposited layermay not be damaged due to a rapid temperature change, and thus a processefficiency may be excellent.

Next, preparation of the hardmask composition including the precursor ofthe 2-dimensional carbon nanostructure will be described. The2-dimensional carbon nanostructure precursor may be i) a 2-dimensionalcarbon nanostructure having less than 0.01 atom % of oxygen or ii) anoxygen free 2-dimensional carbon nanostructure.

In example embodiments, the 2-dimensional carbon nanostructure precursormay be, for example, expanded graphite obtained from exfoliatedgraphite. When expanded graphite is used as the 2-dimensional carbonnanostructure precursor, self-agglomeration of carbon layersconstituting the 2-dimensional carbon nanostructure is suppressed, andthus the 2-dimensional carbon nanostructure may be evenly dispersed inthe hardmask composition without adding an additive such as a dispersingagent or a surfactant so that the hardmask thus prepared may haveexcellent etching resistance, and a process for removing unnecessaryhardmask patterns after forming a to-be-etched layer pattern may beeasy, where a residue such as a carbon residue may not be produced inthe process.

In example embodiments, a 2-dimensional carbon nanostructure precursormay have a structure that is formed of carbon layers obtained byperforming a liquid exfoliating process using a solvent on expandedgraphite.

The carbon layers may include different number of layers, for example,one layer to three hundred layers. For example, the carbon layers mayinclude one layer to sixty layers, one layer to fifteen layers, or onelayer to ten layers.

FIG. 2 illustrates a method of preparing a hardmask composition on ato-be-etched layer according to example embodiments.

Referring to FIG. 2, in operations S200 and S210, a hardmask accordingto example embodiments may be prepared by coating the to-be-etched layerwith the hardmask composition including the 2-dimensional carbonnanostructure precursor and a solvent (S200) and then oxidizing orreducing the coated product (S210).

The oxidizing or reducing the coated product may be controlled until thecoated product is transformed to a hardmask including the 2-dimensionalcarbon nanostructure containing a desired oxygen content (e.g., about0.01 atom % to about 40 atom % of oxygen).

In operation S220, a heat-treating process may be performed afteroxidizing or reducing the coated product. Conditions for theheat-treating process may vary depending on a material of theto-be-etched layer, but a temperature of the heat-treating process maybe from room temperature (in a range of about 20° C. to about 25° C.) toabout 1500° C. The heat-treating process may be performed in an inertgas atmosphere and/or in vacuum. A heating source of the heat-treatingprocess may be induction heating, radiant heat, lasers, infrared rays,microwaves, plasma, ultraviolet rays, or surface plasmon heating. Theinert gas atmosphere may be prepared by mixing a nitrogen gas and/or anargon gas.

After the heat-treating process, in operation S230, the solvent may beremoved. In operation S240, the resultant from which the solvent isremoved may be baked at a temperature of about 100° C. to about 400° C.Then, in operation S250, another heat-treating process may be performedon the baked resultant at a temperature of about 400° C. to about 1,000°C.

When the temperatures of the heat-treating process and the bakingprocess are within these ranges above, hardmasks with excellent etchingresistance may be prepared. A temperature increasing rate in theheat-treating process and the baking process may be about 1° C./min toabout 1000° C./min. When a temperature increasing rate is within thisrange, the deposited layer may not be damaged due to a rapid temperaturechange, and thus a process efficiency may be excellent.

FIG. 3 illustrates a method of preparing a hardmask composition on ato-be-etched layer according to example embodiments.

Referring to FIG. 3, in operations S300 and S310, a hardmask accordingto example embodiments may be prepared by oxidizing or reducing thehardmask composition including the 2-dimensional carbon nanostructureprecursor and a solvent (S300) and then coating the to-be-etched layerwith the oxidized or reduced product (S310). The oxidizing or reducingthe coated product may be controlled until the hardmask including the2-dimensional carbon nanostructure precursor is transformed to ahardmask including the 2-dimensional carbon nanostructure containing adesired oxygen content (e.g., about 0.01 atom % to about 40 atom % ofoxygen).

In operation S320, a heat-treating process may be performed aftercoating the hardmask composition on the to-be-etched layer. Conditionsfor the heat-treating process may vary depending on a material of theto-be-etched layer, but a temperature of the heat-treating process maybe from room temperature (in a range of about 20° C. to about 25° C.) toabout 1500° C. The heat-treating process may be performed in an inertgas atmosphere and/or in vacuum. A heating source of the heat-treatingprocess may be induction heating, radiant heat, lasers, infrared rays,microwaves, plasma, ultraviolet rays, or surface plasmon heating. Theinert gas atmosphere may be prepared by mixing a nitrogen gas and/or anargon gas.

After the heat-treating process, in operation S330, the solvent may beremoved. In operation S340, the resultant from which the solvent isremoved may be baked at a temperature of about 100° C. to about 400° C.Then, in operation S350, another heat-treating process may be performedon the baked resultant at a temperature of about 400° C. to about 1,000°C.

When the temperatures of the heat-treating process and the bakingprocess are within these ranges above, hardmasks with excellent etchingresistance may be prepared. A temperature increasing rate in theheat-treating process and the baking process may be about 1° C./min toabout 1000° C./min. When a temperature increasing rate is within thisrange, the deposited layer may not be damaged due to a rapid temperaturechange, and thus a process efficiency may be excellent.

FIG. 4 illustrates a method of preparing a hardmask composition on ato-be-etched layer according to example embodiments.

A hardmask according to example embodiments may be prepared bysimultaneously coating the to-be-etched layer with the hardmaskcomposition including the 2-dimensional carbon nanostructure precursorand a solvent and oxidizing or reducing the hardmask composition. Theoxidizing or reducing the hardmask composition including the2-dimensional carbon nanostructure precursor and solvent may becontrolled until the hardmask including the 2-dimensional carbonnanostructure precursor is transformed to a hardmask including the2-dimensional carbon nanostructure containing a desired oxygen content(e.g., about 0.01 atom % to about 40 atom % of oxygen).

In operation S410, a heat-treating process may be performed aftercoating the hardmask composition on the to-be-etched layer. Conditionsfor the heat-treating process may vary depending on a material of theto-be-etched layer, but a temperature of the heat-treating process maybe from room temperature (in a range of about 20° C. to about 25° C.) toabout 1500° C. The heat-treating process may be performed in an inertgas atmosphere and/or in vacuum. A heating source of the heat-treatingprocess may be induction heating, radiant heat, lasers, infrared rays,microwaves, plasma, ultraviolet rays, or surface plasmon heating. Theinert gas atmosphere may be prepared by mixing a nitrogen gas and/or anargon gas.

After the heat-treating process, in operation S420, the solvent may beremoved. In operation S430, the resultant from which the solvent isremoved may be baked at a temperature of about 100° C. to about 400° C.Then, in operation S440, another heat-treating process may be performedon the baked resultant at a temperature of about 400° C. to about 1,000°C.

When the temperatures of the heat-treating process and the bakingprocess are within these ranges above, hardmasks with excellent etchingresistance may be prepared. A temperature increasing rate in theheat-treating process and the baking process may be about 1° C./min toabout 1000° C./min. When a temperature increasing rate is within thisrange, the deposited layer may not be damaged due to a rapid temperaturechange, and thus a process efficiency may be excellent.

As described above, when the 2-dimensional carbon nanostructureprecursor is a 2-dimensional carbon nanostructure containing more than40 atom % of oxygen, a hardmask may be prepared by i) coating theto-be-etched layer with the hardmask composition and then reducing thecoated resultant, ii) reducing the hardmask composition and then coatingthe to-be-etched layer with the reduced hardmask composition, or iii)simultaneously coating the to-be-etched layer with hardmask compositionand reducing the hardmask composition. The 2-dimensional carbonnanostructure containing more than 40 atom % of oxygen may contain, forexample, about 60 atom % to about 80 atom % of oxygen.

As described above, when the 2-dimensional carbon nanostructureprecursor contains less than 0.01 atom % of oxygen, a hardmask may beprepared by i) coating the to-be-etched layer with the hardmaskcomposition and then oxidizing the coated resultant, ii) oxidizing thehardmask composition and then coating the to-be-etched layer with theoxidized hardmask composition, or iii) simultaneously coating theto-be-etched layer with the hardmask composition and oxidizing thehardmask composition.

The reducing process may be performed by chemical reduction,heat-treatment reduction, or electrochemical reduction.

The chemical reduction is performed by using a reducing agent. Also, thereduction caused by heat-treatment may be performed by heat-treatment ata temperature of about 100° C. to about 1500° C.

Non-limiting examples of the reducing agent may include at least oneselected from the group consisting of ammonia-borane, hydrazine, sodiumborohydride, dimethylhydrazine, sulfuric acid, hydrochloric acid,hydrogen iodide, hydrogen bromide, hydrogen sulfide, hydroquinone,hydrogen, and acetic acid.

When ammonia-borane is used as reducing agent, a hardmask composition,of which an oxygen content and sp² bond network are controlled may beprepared by i) coating the to-be-etched layer with the hardmaskcomposition and then reducing the coated resultant, ii) reducing thehardmask composition and then coating the to-be-etched layer with thereduced hardmask composition, or iii) simultaneously coating theto-be-etched layer with the hardmask composition and reducing thehardmask composition.

Chemical reduction may be performed by removing a reducing agent fromthe reduced resultant after reducing a precursor of the 2-dimensionalcarbon nanostructure. The reducing agent is removed since degassingduring an etching process may occur when residues such as sodium orpotassium are remained in the reduced resultant.

However, when ammonia-borane is used as a reducing agent, ammonia-boranereadily decomposes at a low temperature, and thus almost no residueremains in the reduced resultant without a process for removing thereducing agent. Therefore, removing the reducing agent is not needed.

In example embodiments, when ammonia-borane is used as a reducing agent,an amount of the residues such as sodium or potassium in the reducedresultant is 5 atom % or less, for example, about 0.000001 to about 5atom %. Here, the amount of residues may be confirmed by XPS.

When ammonia-borane is used as a reducing agent, a hardmask may beprepared by reducing a hardmask composition including a 2-dimensionalcarbon nanostructure precursor and then coating a to-be-etched layerwith the reduced resultant.

In example embodiments, when ammonia-borane is used as a reducing agent,a hardmask may be prepared by simultaneously coating a to-be-etchedlayer with a hardmask composition including a 2-dimensional carbonnanostructure precursor and reducing the hardmask composition.

An oxygen content and sp² bond network of the 2-dimensional carbonnanostructure precursor contained in the hardmask may be controlled byheat-treatment after the reducing of the hardmask composition during theprocess of preparing a hardmask. Here, performing the heat-treatment isoptional.

A type of the heat-treatment may vary depending on a property of asubstrate on which the hardmask in formed. For example, theheat-treatment may be performed at a temperature in a range of about 60°C. to about 400° C., for example, about 80° C. to about 400° C. When theheat-treatment is performed at a temperature within this range, ahardmask may have excellent etching resistance and mechanical strengthand may be easily removed after an etching process without deteriorationof efficiency of the process.

The oxidizing process may be performed by using at least one selectedfrom acid, an oxidizing agent, UV, ozone, IR, heat-treatment, andplasma.

Examples of the acid may include sulfuric acid, nitric acid, aceticacid, phosphoric acid, hydrofluoric acid, perchloric acid,trifluoroacetic acid, hydrochloric acid, m-chlorobenzoic acid, and amixture thereof. Also, examples of the oxidizing agent may includepotassium permanganate, potassium perchlorate, ammonium persulfate, anda mixture thereof.

Hereinafter, a process of preparing a hardmask by using a 2-dimensionalcarbon nanostructure precursor according to example embodiments or a2-dimensional carbon nanostructure obtained therefrom will be describedin detail.

First, an interlayer insertion material may be intercalated intographite to obtain exfoliated graphite; expanded graphite, which is a2-dimensional carbon nanostructure precursor, may be obtained from theexfoliated graphite; and thus a composition including the 2-dimensionalcarbon nanostructure precursor may be obtained.

The expanded graphite may be obtained in the process of applyingultrasonic waves or microwaves to the exfoliated graphite or milling theexfoliated graphite. Here, the process of milling the exfoliatedgraphite may be performed by using a ball mill or a mono-planar mill.

Optionally, a liquid exfoliating process including dispersion in asolvent may be performed on the expanded graphite. When the liquidexfoliating process is performed on the expanded graphite, a2-dimensional carbon nanostructure precursor including one layer toseveral tens layers of carbon layer (e.g., about 20 to about 70 layersof carbon layer) may be obtained.

The interlayer insertion material may be at least one selected fromsulfuric acid, chromic acid, and ions such as potassium or sodium or anion-containing compound.

Examples of the solvent in the liquid exfoliating process may beN-methylpyrrolidone, ethanol, and water. Also, ultrasonic waves may beused for the dispersion in the liquid exfoliating process. For example,the dispersion process in the solvent may be performed for about 0.5hour to about 30 hours.

In example embodiments, when the expanded graphite is obtained byapplying ultrasonic waves to the exfoliated graphite, a frequency of theultrasonic waves may be in a range of about 20 KHz to about 60 KHz.

In example embodiments, when the expanded graphite is obtained byapplying microwaves to the exfoliated graphite, an output of themicrowaves may be about 50 W to about 1500 W, and a frequency of themicrowaves may be in a range of about 2.45 KHz to about 60 KHz. A periodof time for applying the microwaves may vary depending on the frequencyof the microwaves but may be, for example, about 10 minutes to about 30minutes.

Examples of graphite used as a starting material may include naturalgraphite, kish graphite, synthetic graphite, expandable graphite orexpanded graphite, and a mixture thereof.

The hardmask composition thus obtained may be used to form a2-dimensional carbon nanostructure layer, and then, according to aprocess of oxidizing the layer, a hardmask including a 2-dimensionalcarbon nanostructure having an oxygen content of about 0.01 atom % toabout 40 atom % may be obtained. The 2-dimensional carbon nanostructurelayer obtained in this manner may have no defect, and a hardmaskincluding the 2-dimensional carbon nanostructure layer may haveexcellent etching resistance.

Second, the graphite may be acid-treated. For example, an acid or anoxidizing agent may be added to the graphite, heated to allow thereaction, and cooled to room temperature (about 20° C. to about 25° C.)to obtain a mixture containing a 2-dimensional carbon nanostructureprecursor. An oxidizing agent is added to the precursor-containingmixture to perform an oxidizing process, and thus a 2-dimensional carbonnanostructure having about 0.01 atom % to about 40 atom % of oxygen maybe obtained.

The 2-dimensional carbon nanostructure precursor may include less thanabout 0.01 atom % of oxygen or may not contain oxygen.

The oxidizing agent, a concentration of an acid solution, and a treatingtime in the oxidizing process may be adjusted to control the oxygencontent.

Examples of the acid and the oxidizing agent are as described above. Anamount of the oxidizing agent may be, for example, about 0.00001 part toabout 30 parts by weight based on 100 parts by weight of the graphite.

Third, in the preparation process, the 2-dimensional carbonnanostructure precursor is oxidized to the maximum to obtain acomposition containing a 2-dimensional carbon nanostructure precursorhaving more than 40 atom % of oxygen, and a 2-dimensional carbonnanostructure precursor layer is formed by using the composition. Forexample, an oxygen content in the 2-dimensional carbon nanostructureprecursor may be about 80 atom % to about 90 atom %. The layer thusformed may be reduced, and thus a hardmask containing a 2-dimensionalcarbon nanostructure containing about 0.01 atom % to about 40 atom % ofoxygen may be prepared.

The oxidizing process in the preparation process may be performed byusing at least one selected from acid, an oxidizing agent, UV(ultraviolet), ozone, IR (infrared), heat-treatment, and plasma. Here,the acid and the oxidizing agent may be as described above.

Heat-treatment may be performed during or after the process of coatingthe to-be-etched layer with the hardmask composition. Here, atemperature of the heat-treatment differs depending on a purpose of theheat-treatment but may be, for example, in a range of about 100° C. toabout 1500° C.

Hereinafter, a method of forming a pattern by using a hardmaskcomposition according to example embodiments will be described byreferring to FIGS. 5A to 5E.

Referring to FIG. 5A, a to-be-etched layer 11 may be formed on asubstrate 10. A hardmask composition including a 2-dimensional carbonnanostructure that contains about 0.01 atom % to about 40 atom % ofoxygen or a 2-dimensional carbon nanostructure precursor thereof and asolvent may be provided on the to-be-etched layer 11 to form a hardmask12.

A process of providing the hardmask composition maybe performed by onemethod selected from spin coating, air spraying, electrospraying, dipcoating, spray coating, doctor blade coating, and bar coating.

In example embodiments, the hardmask composition may be provided byusing a spin-on coating method. Here, the hardmask composition may coatthe substrate 10 at a thickness of, for example, in a range of about 10nm to about 10,000 nm, or, about 10 nm to about 1,000 nm, but thethickness of the hardmask composition is not limited thereto.

A material of the substrate 10 is not particularly limited, and thesubstrate may be at least one selected from, for example, a Sisubstrate; a glass substrate; a GaN substrate; a silica substrate; asubstrate including at least one selected from nickel (Ni), cobalt (Co),iron (Fe), platinum (Pt), palladium (Pd), gold (Au), aluminum (Al),chromium (Cr), copper (Cu), manganese (Mn), molybdenum (Mo), rhodium(Rh), iridium (Ir), tantalum (Ta), titanium (Ti), tungsten (W), uranium(U), vanadium (V), and zirconium (Zr); and a polymer substrate. Thesubstrate 10 may be semiconductor-on-insulator (SOI) substrate such as asilicon-on-insulator substrate.

A photoresist layer 13 may be formed on the hardmask 12.

As shown in FIG. 5B, a photoresist pattern 13 a may be formed byexposing and developing the photoresist layer 13 by using a commonmethod in the art.

The process of exposing the photoresist layer 13 may be performed byusing, for example, ArF, KrF, or EUV. Also, after the exposing process,a heat-treating process at a temperature in a range of about 200° C. toabout 500° C. may be performed on the exposed photoresist layer 13.

In the developing process, a developing solution such as an aqueoussolution of tetramethylammonium hydroxide (TMAH) may be used.

Thereafter, the hardmask 12 may be etched by using the photoresistpattern 13 a as an etching mask to form a hardmask pattern 12 a on theto-be-etched layer 11 (FIG. 5C).

A thickness of the hardmask pattern 12 a may be in a range of about 10nm to about 10,000 nm. When the thickness of the hardmask pattern 12 ais within this range, the hardmask pattern 12 a may have excellentetching resistance as well as excellent homogenousness.

For example, the etching process may be performed by using a dry etchingmethod using an etching gas. Examples of the etching gas include afluorine-containing and/or a chlorine-containing gas. For example, theetching gas may include at least one of CF₄, C₂F₆, C₄F₈, CHF₃, Cl₂, andBCl₃, but example embodiments are not limited thereto

In example embodiments, when a mixture gas of C₄F₈ and CHF₃ is used asthe etching gas, a mixing ratio of C₄F₈ and CHF₃ may be in a range ofabout 1:10 to about 10:1 at a volume ratio.

The to-be-etched layer 11 may be formed as a plurality of patterns. Theplurality of patterns may vary, for example, may be a metal pattern, asemiconductor pattern, and an insulator pattern. For example, theplurality of patterns may be various patterns applied to a semiconductorintegrated circuit device.

The to-be-etched layer 11 may contain a material that is to be finallypatterned. The material of the to-be-etched layer 11 may be, forexample, a metal such as aluminum or copper, a semiconductor such assilicon, or an insulator such as silicon oxide or silicon nitride. Theto-be-etched layer 11 may be formed by using various methods such assputtering, electronic beam deposition, chemical vapor deposition, andphysical vapor deposition. For example, the to-be-etched layer 11 may beformed by using a chemical vapor deposition method.

As shown in FIGS. 5D to 5E, the to-be-etched layer 11 may be etched byusing the hardmask pattern 12 a as an etching mask to later form ato-be-etched layer pattern 11 a having a desired fine pattern.

In example embodiments, the hardmask may be used as a stopper in themanufacture of a semiconductor device by being inserted between otherlayers.

FIG. 5F illustrates a part of method of forming a pattern by using ahardmask composition according to example embodiments.

Referring to FIG. 5F, as previously-described with reference to FIG. 5A,a to-be-etched layer 11 may be formed on a substrate 10 and a hardmask12 may be formed on the to-be-etched layer 11. Then, aspreviously-described with reference to FIG. 5B, a photoresist pattern 13a may be formed on the hardmask 12. Thereafter, the hardmask 12 may beetched using the photoresist pattern 13 a as an etching mask to form ahardmask pattern 12 a on the to-be etched layer 11. As shown in FIG. 5F,a portion of the photoresist pattern 13 a may remain after the hardmaskpattern 12 a is formed.

Then, the to-be-etched layer 11 may be etched to form an etched layerpattern 11 a having a desired fine pattern using a remaining portion ofthe photoresist pattern 13 a and the hardmask pattern 12 a as an etchingmask. Afterwards, the hardmask pattern 12 a and any residual portion ofphotoresist pattern 13 a may be removed using O₂ ashing and/or wetstripping to form a structure including the etched layer pattern 11 a onthe substrate 10 (see FIG. 5E). For example, the wet stripping may beperformed by using alcohol, acetone, or a mixture of nitric acid andsulfuric acid.

Hereinafter, a method of forming a pattern by using a hardmaskcomposition according to example embodiments, will be described byreferring to FIGS. 6A to 6D.

Referring to FIG. 6A, a to-be-etched layer 21 is formed on a substrate20. The substrate 20 may be a silicon substrate, but is not limited toand may be any of the materials previously described as suitable for thesubstrate 10 in FIG. 5A.

The to-be-etched layer 21 may be formed as, for example, a silicon oxidelayer, a silicon nitride layer, a silicon nitroxide layer, a siliconoxynitride (SiON) layer, a silicon carbide (SiC) layer, or a derivativelayer thereof.

Thereafter, a hardmask composition may be provided on the to-be-etchedlayer 21 to form a hardmask 22. In other words, a hardmask compositionincluding a 2-dimensional carbon nanostructure that contains about 0.01atom % to about 40 atom % of oxygen or a 2-dimensional carbonnanostructure precursor thereof and a solvent may be provided on theto-be-etched layer 21 to form a hardmask 22.

An anti-reflection layer 30 may be formed on the hardmask 22. Here, theanti-reflection layer 30 may include an inorganic anti-reflection layer,an organic anti-reflection layer, or a combination thereof. FIGS. 6A to6C illustrate cases where the anti-reflection layer 30 includes aninorganic anti-reflection layer 32 and an organic anti-reflection layer34.

The inorganic anti-reflection layer 32 may be, for example, a SiONlayer, and the organic anti-reflection layer 34 may be a polymer layercommonly used in the art having an appropriate refraction index and ahigh absorption coefficient on a photoresist with respect to awavelength of light.

A thickness of the anti-reflection layer 30 may be, for example, in arange of about 100 nm to about 500 nm.

A photoresist layer 23 is formed on the anti-reflection layer 30.

The photoresist layer 23 is exposed and developed in a common manner toform a photoresist pattern 23 a. Then, the anti-reflection layer 30 andthe hardmask 22 are sequentially etched by using the photoresist pattern23 a as an etching mask to form a hardmask pattern 22 a on theto-be-etched layer 21. The hardmask pattern 22 a includes an inorganicanti-reflection layer pattern 32 a and an organic anti-reflection layerpattern 34 a.

FIG. 6B illustrates that the photoresist pattern 23 a and ananti-reflection layer pattern 30 a remain after forming the hardmaskpattern 22 a. However, in some cases, part of or the whole photoresistpattern 23 a and the anti-reflection layer pattern 30 a may be removedafter the etching process for forming the hardmask pattern 22 a.

FIG. 6C illustrates that only the photoresist pattern 23 a may beremoved.

The to-be-etched layer 21 may be etched by using the hardmask pattern 22a as an etching mask to form a desired layer pattern, which is ato-be-etched layer pattern 21 a (FIG. 6D).

As described above, the hardmask pattern 22 a is removed after formingthe to-be-etched layer pattern 21. In the preparation of the hardmaskpattern according to example embodiments, the hardmask pattern 22 a maybe easily removed by using a common method in the art, and almost noresidue remains after removing the hardmask pattern 22 a.

The removing process of the hardmask pattern 22 a may be performed by,but not limited to, O₂ ashing and wet stripping. For example, the wetstripping may be performed by using alcohol, acetone, or a mixture ofnitric acid and sulfuric acid.

A 2-dimensional carbon nanostructure of a hardmask prepared in themanner described above is a structure having 2-dimensionalnanocrystalline carbon layers stacked in a direction of a z-axis. Also,the 2-dimensional carbon nanostructure may have a thickness of about 100nm or less, a length of about 500 nm to about 50 μm. Also, an aspectratio (a ratio of the longest diameter to the shortest diameter) of the2-dimensional carbon nanostructure may be at least 50.

The hardmask includes a 2-dimensional carbon nanostructure containingabout 0.01 atom % to about 40 atom % of oxygen, and the amount of sp²carbon structures is higher than the amount of sp³ carbon structures inthe hardmask. Thus, the hardmask may secure sufficient resistance to dryetching.

FIGS. 7A to 7D illustrate a method of forming a pattern by using ahardmask composition according to example embodiments.

Referring to FIG. 7A, a to-be-etched layer 61 may be formed on asubstrate 60. Then, a hardmask 62 may be formed on the to-be-etchedlayer 61 and a first photoresist pattern 63 a may be formed on thehardmask 62.

A material of the substrate 60 is not particularly limited, and thesubstrate may be at least one selected from, for example, a Sisubstrate; a glass substrate; a GaN substrate; a silica substrate; asubstrate including at least one selected from nickel (Ni), cobalt (Co),iron (Fe), platinum (Pt), palladium (Pd), gold (Au), aluminum (Al),chromium (Cr), copper (Cu), manganese (Mn), molybdenum (Mo), rhodium(Rh), iridium (Ir), tantalum (Ta), titanium (Ti), tungsten (W), uranium(U), vanadium (V), and zirconium (Zr); and a polymer substrate. Thesubstrate 60 may be semiconductor-on-insulator (SOI) substrate such as asilicon-on-insulator substrate.

The to-be-etched layer 61 may be formed as, for example, a silicon oxidelayer, a silicon nitride layer, a silicon nitroxide layer, a siliconoxynitride (SiON) layer, a silicon carbide (SiC) layer, or a derivativelayer thereof. However, example embodiments are not limited thereto.

Thereafter, a hardmask composition may be provided on the to-be-etchedlayer 61 to form a hardmask 62. In other words, a hardmask compositionincluding a 2-dimensional carbon nanostructure that contains about 0.01atom % to about 40 atom % of oxygen or a 2-dimensional carbonnanostructure precursor thereof and a solvent may be provided on theto-be-etched layer 61 to form a hardmask 62.

Thereafter, as shown in FIG. 7B, a second photoresist pattern 63 b maybe formed on top of the hardmask 62. The first and second photoresistpatterns 63 a and 63 b may be alternately arranged.

In FIG. 7C, the hardmask layer 62 may be etched using the photoresistpatterns 63 a and 63 b as an etch mask to form a hardmask pattern 62 a.Then, in FIG. 7D, the to-be etched layer 61 may be etched to form ato-be-etched layer pattern 61 a.

Even though FIGS. 7C and 7D illustrate the first and second photoresistpatterns 63 a and 63 b remain on top of the hardmask pattern 62 a afterforming the hardmask pattern 62 a, example embodiments are not limitedthereto. A portion and/or an entire portion of the first and secondphotoresist patterns 63 a and 63 b may be removed during (and/or after)the process of forming the hardmask pattern 62 a and/or the to-be-etchedlayer 61 a in FIGS. 7C and 7D.

FIGS. 8A to 8D illustrate a method of forming a pattern by using ahardmask composition according to example embodiments.

Referring to FIG. 8A, as previously described with reference to FIG. 6A,a stacked structure including the substrate 20, to-be-etched layer 21,hardmask layer 22, anti-reflection layer 30, and photoresist layer 23may be formed.

Thereafter, the photoresist layer may be exposed and developed in acommon manner to form a photoresist pattern 23 a. The anti-reflectionlayer 30 may be etched by using the photoresist pattern 23 a as anetching mask to form an anti-reflection layer pattern 30 a on theto-be-etched layer 21. The anti-reflection layer pattern 30 a mayinclude an inorganic anti-reflection layer pattern 32 a and an organicanti-reflection layer pattern 34 a.

As shown in FIG. 8B, a dielectric layer 60 (e.g., silicon oxide) may becoated on the photoresist pattern 23 a.

Referring to FIG. 8C, spacers 62 may be formed by etching the dielectriclayer 60. A hardmask pattern 22 b may be formed by etching the hard masklayer 22 using the photoresist pattern 23 a and spacers 62 as an etchmask.

Referring to FIG. 8D, the photoresist pattern 23 a and anti-reflectionlayer pattern 30 a may be removed using the spacers 62 as an etch mask.Next, a second hardmask pattern 22 c may be formed by etching thehardmask pattern 22 b using the spacers as an etch mask.

Thereafter, the to-be-etched layer 21 may be etched to form a patterncorresponding to the second hardmask pattern 22 c using the spacers 62and the second hardmask pattern 22 c as an etch mask. Additionally, thespacers 62 and second hardmask pattern 22 c may be subsequently removedafter patterning the to-be-etched layer 21.

According to example embodiments, a pattern formed by using a hardmaskcomposition may be used in the manufacture and design of an integratedcircuit device according to a preparation process of a semiconductordevice. For example, the pattern may be used in the formation of apatterned material layer structure such as metal lining, holes forcontact or bias, insulation sections (example: a Damascene Trench (DT)or shallow trench isolation (STI)), or a trench for a capacitorstructure.

The present disclosure will be described in further detail withreference to the following examples. These examples are for illustrativepurposes only and are not intended to limit the scope of exampleembodiments.

Example 1

10 g of graphite powder was added to 50 ml of sulfuric acid (H₂SO₄) andstirred for about 4 hours to about 5 hours at a temperature of about 80°C. The stirred mixture was diluted with 1 L of deionized water andstirred for about 12 hours. The resultant was filtered to obtainpre-treated graphite.

Phosphorus pentoxide (P₂O₅) was dissolved in 80 ml of water, 480 ml ofsulfuric acid was added, 4 g of the pre-treated graphite was added, andthen 24 g of potassium permanganate (KMnO₄) was added thereto. Afterstirring the mixture, about 1 hour of sonication was performed thereonand 600 ml of water (H₂O) was added thereto. When 15 ml of hydrogenperoxide (H₂O₂) was added to the obtained reaction mixture, the color ofthe reaction mixture turned from purple to light yellow and sonicationwas performed thereon while stirring the mixture. The reaction mixturewas filtered to remove residual graphite that is not oxidized. In orderto remove manganese (Mn) from the filtered solution obtained after thefiltration, 200 ml of hydrochloric acid, 200 ml of ethanol, and 200 mlof water were added to the filtered solution, and the mixture wasstirred. The stirred mixture was centrifuged to obtain a 2-dimensionalcarbon nanostructure precursor. Here, a content of the oxygen in the2-dimensional carbon nanostructure precursor was 30 atom %.

0.5 g of the 2-dimensional carbon nanostructure precursor thus obtainedwas dispersed in 1 L of water to obtain a hardmask composition.Heat-treatment was performed at a temperature of about 200° C. whilespray coating the hardmask composition on a silicon oxide layer formedon a silicon substrate. Subsequently, the resultant was baked at atemperature of about 400° C. for about 1 hour and then vacuumheat-treated at a temperature of about 600° C. for about 1 hour to forma hardmask containing a 2-dimensional carbon nanostructure and having athickness of about 200 nm.

The hardmask was coated with an ArF photoresist at a thickness of about1700 Å and then pre-baked at a temperature of about 110° C. for about 60seconds. The resultant was then exposed to light by using a lightexposing instrument available from ASML (XT: 1400, NA 0.93) andpost-baked at a temperature of about 110° C. for about 60 seconds. Next,the photoresist was developed by using an aqueous solution of 2.38 wt %TMAH (tetramethyl ammonium hydroxide) to form a photoresist pattern.

Dry etching was performed using the photoresist pattern, as a mask, anda CF₄/CHF₃ mixture gas. The etching conditions included 20 mT of achamber pressure, 1800 W of a RF power, a 4/10 volume ratio ofC₄F₈/CHF₃, and an etching time of about 120 seconds.

O₂ ashing and wet stripping were performed on a hardmask and an organicmaterial remaining after performing the dry etching to obtain a desiredsilicon substrate having a silicon oxide layer pattern as a finalpattern.

Example 2

A silicon substrate having a silicon oxide layer pattern was prepared inthe same manner as in Example 1, except that a vacuum heat-treatmenttemperature was 850° C.

Example 3

A silicon substrate having a silicon oxide layer pattern was prepared inthe same manner as in Example 1, except that a vacuum heat-treatmenttemperature was 400° C.

Example 4

A silicon substrate having a silicon oxide layer pattern was prepared inthe same manner as in Example 1, except that a vacuum heat-treatmenttemperature was 900° C.

Example 5

A silicon substrate having a silicon oxide layer pattern was prepared inthe same manner as in Example 1, except that the process of preparingthe 2-dimensional carbon nanostructure precursor was controlled toobtain a hardmask including a 2-dimensional carbon nanostructurecontaining about 0.01 atom % of oxygen.

Example 6

A silicon substrate having a silicon oxide layer pattern was prepared inthe same manner as in Example 1, except that the process of preparingthe 2-dimensional carbon nanostructure precursor was controlled toobtain a hardmask including a 2-dimensional carbon nanostructurecontaining about 40 atom % of oxygen.

Example 7

A silicon substrate, on which a silicon oxide is formed, was primaryspray coated with ½ of the hardmask composition prepared in Example 1while performing heat-treatment at a temperature of about 200° C. Here,a content of the oxygen in the 2-dimensional carbon nanostructureprecursor was 30 atom %.

Subsequently, the resultant was baked at a temperature of about 400° C.for about 1 hour, and then primary vacuum heat-treatment was performedthereon at a temperature of about 400° C. for about 1 hour.

Next, the vacuum heat-treated resultant was spray-coated with the other½ of the hardmask composition prepared in Example 1 while performingheat-treatment at a temperature of about 200° C. Subsequently, theresultant was baked at a temperature of about 400° C. for about 1 hour,and then secondary vacuum heat-treatment was performed thereon at atemperature of about 400° C. for about 1 hour to form a hardmaskcontaining a 2-dimensional carbon nanostructure and having a thicknessof about 200 nm.

Example 8

0.5 g of the 2-dimensional carbon nanostructure precursor prepared inExample 1 was dispersed in 1 L of water, and 0.5 g of ammonia-borane wasadded thereto and then the resultant was reduced at a temperature ofabout 80° C. to prepare a hardmask composition. The hardmask compositionwas vapor-deposited on the silicon substrate, on which a silicon oxideis formed, at a temperature of about 200° C. to form a hardmaskcontaining a 2-dimensional carbon nanostructure and having a thicknessof about 200 nm. An amount of oxygen in the 2-dimensional carbonnanostructure was about 16 atom %.

Comparative Example 1

A silicon substrate having a silicon oxide layer pattern was prepared byusing a hardmask including high-temperature amorphous carbon.

A carbon source (C₃H₆) was vapor-deposited on the silicon oxide layerformed on the silicon substrate to form a hardmask includinghigh-temperature amorphous carbon.

The vapor deposition was performed by using a chemical vapor depositionmethod under conditions including a temperature of about 550° C., apressure of about 0.05 mTorr, and an ion energy of about 250 eV.

The hardmask was coated with an ArF photoresist at a thickness of about1700 Å and then pre-baked at a temperature of about 110° C. for about 60seconds. The resultant was then exposed to light by using a lightexposing instrument available from ASML (XT: 1400, NA 0.93) andpost-baked at a temperature of about 110° C. for about 60 seconds. Next,the photoresist was developed by using an aqueous solution of 2.38 wt %TMAH to form a photoresist pattern.

Dry etching was performed using the photoresist pattern, as a mask, anda CF₄/CHF₃ mixture gas. The etching conditions included 20 mT of achamber pressure, 1800 W of a RT power, a 4/10 volume ratio ofC₄F₈/CHF₃, and an etching time of about 120 seconds.

O₂ ashing and wet stripping were performed on the hardmask and anorganic material remaining after performing the dry etching to obtain adesired silicon substrate having a silicon oxide layer pattern as afinal pattern.

Comparative Example 2

A silicon substrate having a silicon oxide layer pattern was prepared byusing a hardmask including low-temperature amorphous carbon in the samemanner as in Comparative Example 1, except that a temperature of adeposition condition for the carbon source (C₃H₆) was changed to 300° C.to obtain low-temperature amorphous carbon.

Comparative Example 3

A monomer represented by Formula 1 below was dissolved in a mixturesolvent including propylene glycol monomethyl ether acetate (PGMEA),N-methylpyrrolidone, and gamma-butyrolactone (at a volume ratio of40:20:40), and the solution was filtered to prepare a hardmaskcomposition:

A silicon substrate having a silicon oxide layer pattern was coated withthe hardmask composition obtained in the manner described above by usinga spin-on coating method, and then the resultant was heat-treated at atemperature of about 400° C. for about 120 seconds to form a hardmaskincluding spin-on-carbon (SOC).

The hardmask was coated with an ArF photoresist at a thickness of about1700 Å and then pre-baked at a temperature of about 110° C. for about 60seconds. The resultant was then exposed to light by using a lightexposing instrument available from ASML (XT: 1400, NA 0.93) andpost-baked at a temperature of about 110° C. for about 60 seconds. Next,the photoresist was developed by using an aqueous solution of 2.38 wt %TMAH to form a photoresist pattern.

Dry etching was performed using the photoresist pattern as a mask and aCF₄/CHF₃ mixture gas. The etching conditions included 20 mT of a chamberpressure, 1800 W of a RF power, a 4/10 volume ratio of C₄F₈/CHF₃, and anetching time of about 120 seconds.

O₂ ashing and wet stripping were performed on the hardmask and anorganic material remaining after performing the dry etching to obtain adesired silicon substrate having a silicon oxide layer pattern as afinal pattern.

Comparative Example 4

A silicon substrate having a silicon oxide layer pattern was prepared inthe same manner as in Example 1, except that the process of preparingthe 2-dimensional carbon nanostructure precursor was controlled toobtain a hardmask including a 2-dimensional carbon nanostructurecontaining about 0.005 atom % of oxygen.

Evaluation Example 1 X-Ray Diffraction (XRD) Analysis Measurement

XRD analysis was performed on the 2-dimensional carbon nanostructuresprepared in Examples 1 to 3 and the high-temperature amorphous carbonprepared in Comparative Example 1. For the XRD analysis, a 12 KW XRDdiffractometer available from BRUKER AXS was used, and the analysisconditions included measurement at a rate of about 4° per minute withina range of about 5° to about 80° as a diffraction angle 2θ.

The analysis results are shown in FIG. 9.

Referring to FIG. 9, it may be confirmed that the diffraction angle 2θof (002) crystal face peaks of the 2-dimensional carbon nanostructuresprepared in Examples 1 to 3 were observed within a range of about 25° toabout 27°, unlike that of the amorphous carbon prepared in ComparativeExample 1. From the results of the XRD analysis of the 2-dimensionalcarbon nanostructures prepared in Examples 1 to 3, d-spacings (d₀₀₂) andaverage particle diameters (La) of the crystals were obtained and areshown in Table 1.

The d-spacings were calculated by using Bragg's law defined in Equation1 below, and the average particle diameters of the crystals werecalculated by using the Scherrer equation defined in Equation 2.

d ₀₀₂=λ/2 sin θ  [Equation 1]

D=(0.9λ)/(β cos θ)  [Equation 2]

In Equations 1 and 2, λ is an X-ray wavelength (1.54 Å) and β is a fullwidth at half maximum (FWHM) at a Bragg's angle.

TABLE 1 d-spacing Average particle diameter (nm) (La) of crystals (Å)Example 1 0.356 28.0 Example 2 0.343 25.1 Example 3 0.334 24.5

Evaluation Example 2 Raman Spectrum Analysis

Raman spectroscopy analysis was performed on the 2-dimensional carbonnanostructures prepared in Examples 1 to 3 and the high-temperatureamorphous carbon prepared in Comparative Example 1. The Ramanspectroscopy analysis results are shown in FIG. 10. The Ramanspectroscopy analysis was performed by using the Raman instrument,RM-1000 Invia (514 nm, Ar⁺ ion laser), available from Renishaw. Here, aD peak, a G peak, and a 2D peak respectively are peaks at about 1340cm⁻¹ to about 1350 cm⁻¹, at about 1580 cm⁻¹, and at about 2700 cm⁻¹.

Referring to FIG. 10, an intensity ratio of a D mode peak to a G modepeak (I_(D)/I_(G)) and an intensity ratio of a 2D mode peak to a G modepeak (I_(2D)/I_(G)) of the 2-dimensional carbon nanostructures preparedin Examples 1 to 3, the high-temperature amorphous carbon prepared inComparative Example 1, and the low-temperature amorphous carbon preparedin Comparative Example 2 were obtained and are shown in Table 2.

TABLE 2 I_(D)/I_(G) I_(2D)/I_(G) Example 1 0.87 0.01 Example 2 0.86 0.02Example 3 0.90 0.1 Comparative 0.85 — Example 1

Table 2 shows the hardmask composition prepared in Examples 1-3 have adifferent structure than the hardmask composition in Comparative Example1.

Evaluation Example 3 XPS Analysis

XPS spectroscopy analysis was performed on the 2-dimensional carbonnanostructures prepared in Examples 1 to 4 and the high-temperatureamorphous carbon prepared in Comparative Example 1 by using a Quantum2000 (Physical Electronics).

The analysis results are shown in Table 3. In theory, ComparativeExample 1 should have no oxygen; however, one of ordinary skill in theart would appreciate that the inclusion of moisture and/or oxygen bypollution and impurities during the XPS analysis may account for theoxygen content corresponding to Comparative Example 1 in Table 3.

TABLE 3 XPS Oxygen content C/O atomic ratio (atom %) C═C/C—C^(a) Example1 6.7 12.7 1.98 Example 2 14.4 6.43 2.29 Example 3 6.9 12.5 2.1 Example4 23.8 3.99 4.2 ^(a)C═C/C—C denotes an intensity ratio of a peakintensity corresponding to a C═C bond and a peak intensity correspondingto a C—C bond, which also shows a ratio of a fraction of sp² to afraction of sp³.

Evaluation Example 4 Etching Resistance

Etching resistance was evaluated by calculating an etching selectionratio by measuring the thickness differences of the hardmask and thesilicon oxide layer before and after performing the dry etching by usingeach of the hardmasks prepared in Examples 2, 3, 7, and 8.

In Table 4, the etching selection ratio shows a ratio of the thicknessdifference of the silicon oxide before and after the etching to thethickness difference of the hard mask before and after the etching.

TABLE 4 Etching selection ratio Example 2 12.2 Example 3 16.0 Example 714.0 Example 8 12.7 Comparative 10.0 Example 1 Comparative 7.0 Example 2Comparative 5.35 Example 3

As shown in Table 4, the etching selection ratios of the hardmasksprepared in Examples 2, 3, 7, and 8 increased, and thus the etchingresistances of the hardmasks prepared in the Examples 2, 3, 7, and 8were improved than those of the hardmasks prepared in ComparativeExamples 1 to 3.

Evaluation Example 5 Pattern Shape Analysis

Etching was performed by using each of the hardmasks prepared inExamples 1 to 8 and Comparative Examples 1 to 3, and then across-section of the silicon substrate having a silicon oxide layerpattern was observed by using FE-SEM, and the results are shown in Table5.

TABLE 5 Shape of pattern after Shape of pattern after hardmask etchingsilicon oxide etching Example 1 Vertical Vertical Example 2 VerticalVertical Example 3 Vertical Vertical Example 4 Vertical Vertical Example5 Vertical Vertical Example 6 Vertical Vertical Example 7 VerticalVertical Example 8 Vertical Vertical Comparative Arched Tapered Example1 Comparative Arched Tapered Example 2 Comparative Arched TaperedExample 3

As shown in Table 5, the silicon oxide layer pattern shapes having eachof the hardmasks prepared in Examples 1 to 8 are vertical, unlike thatof the hardmask prepared in Comparative Examples 1-3.

As described above, hardmasks according to example embodiments may haveexcellent etching resistance and mechanical strength compared to that ofconventional polymers or amorphous carbon and may be easily removedafter an etching process, and accordingly, the efficiency of asemiconductor process may be improved by using the hardmask.

It should be understood that example embodiments described herein shouldbe considered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each hardmaskcomposition, method of making a fine pattern, and/or method of making ahardmask composition respectively should typically be considered asavailable for other similar features or aspects in other hardmaskcompositions, methods of making a fine pattern, and/or methods of makinga hardmask composition according to example embodiments. While someexample embodiments have been particularly shown and described, it willbe understood by those of ordinary skill in the art that various changesin form and details may be made therein without departing from thespirit and scope of the claims.

What is claimed is:
 1. A hardmask composition comprising: a2-dimensional carbon nanostructure containing about 0.01 atom % to about40 atom % of oxygen, an intensity ratio of a D mode peak to a G modepeak obtained by Raman spectroscopy of the 2-dimensional carbonnanostructure being 2 or lower; and a solvent.
 2. The hardmaskcomposition of claim 1, wherein the intensity ratio of the D mode peakto the G mode peak obtained by Raman spectroscopy of the 2-dimensionalcarbon nanostructure precursor is in a range of 0.001 to about 2.0. 3.The hardmask composition of claim 1, wherein a diffraction angle 2θ of a(002) crystal face peak obtained by X-ray diffraction analysis of the2-dimensional carbon nanostructure is observed within a range of about20° to about 27°.
 4. The hardmask composition of claim 1, wherein ad-spacing of the 2-dimensional carbon nanostructure obtained by X-raydiffraction analysis is about 0.3 to about 0.5 nm.
 5. The hardmaskcomposition of claim 1, wherein the 2-dimensional carbon nanostructurehas crystallinity in a C-axis, and an average particle diameter ofcrystals is about 1 nm or greater.
 6. The hardmask composition of claim5, wherein the average particle diameter of crystals is in a range ofabout 23.7 Å to about 43.9 Å.
 7. The hardmask composition of claim 1,wherein a fraction of sp² carbon is equal to or a multiple of a fractionof sp³ carbon in the 2-dimensional carbon nanostructure.
 8. A method offorming a pattern, the method comprising: forming a to-be-etched layeron a substrate; forming a hardmask on the to-be-etched layer bysupplying the hardmask composition of claim 1, the hardmask includingthe 2-dimensional carbon nanostructure; forming a photoresist pattern onthe hardmask; forming a hardmask pattern on the to-be-etched layer byetching the 2-dimensional carbon nanostructure by using the photoresistpattern as an etching mask, the hardmask pattern including the2-dimensional carbon nanostructure; and etching the to-be-etched layerby using the hardmask pattern as an etching mask.
 9. The method of claim8, wherein the forming the hardmask on the to-be-etched layer includescoating the hardmask composition on the to-be-etched layer.
 10. Themethod of claim 9, further comprising: heat-treating the hardmaskcomposition, wherein the heat-treating is performed during or after thecoating the hardmask composition on the to-be-etched layer.
 11. Themethod of claim 8, wherein the 2-dimensional carbon nanostructure of thehardmask pattern is a structure formed by stacking 2-dimensionalnanocrystalline carbon layers.
 12. The method of claim 8, wherein athickness of the hardmask is about 10 nm to about 10,000 nm.
 13. Themethod of claim 8, wherein the step of forming the hardmask on theto-be-etched layer is performed using at least one of spin coating, airspray, electrospray, dip coating, spray coating, a doctor blade method,and bar coating.
 14. The method of claim 8, wherein the to-be-etchedlayer includes one of a metal, a semiconductor, and an insulator. 15.The hardmask composition of claim 1, wherein the solvent includes atleast one of water, methanol, isopropanol, ethanol,N,N-dimethylformamide, N-methylpyrrolidone, dichloroethane,dichlorobenzene, N,N-dimethylsulfoxide, xylene, aniline, propyleneglycol, propylene glycol diacetate, methoxy propanediol, diethyleneglycol, acetyl acetone, cyclohexanone, propylene glycol monomethyl etheracetate, γ-butyrolactone, O-dichlorobenzene, nitromethane,tetrahydrofuran, dimethyl sulfoxide, nitrobenzene, butyl nitrite, methylcellosolve, ethyl cellosolve, diethyl ether, diethylene glycol methylether, diethylene glycol ethyl ether, dipropylene glycol methyl ether,toluene, hexane, methyl ethyl ketone, methyl isobutyl ketone,hydroxymethyl cellulose, and heptane.
 16. A hardmask compositioncomprising: a 2-dimensional carbon nanostructure containing about 0.01atom % to about 40 atom % of oxygen, an intensity ratio of a 2D modepeak to a G mode peak obtained by Raman spectroscopy of the2-dimensional carbon nanostructure being 0.01 or higher; and a solvent.17. The hardmask composition of claim 16, wherein the intensity ratio ofthe 2D mode peak to the G mode peak obtained by Raman spectroscopy ofthe 2-dimensional carbon nanostructure is in a range of about 0.01 toabout 1.0.
 18. The hardmask composition of claim 16, wherein the solventincludes at least one of water, methanol, isopropanol, ethanol,N,N-dimethylformamide, N-methylpyrrolidone, dichloroethane,dichlorobenzene, N,N-dimethylsulfoxide, xylene, aniline, propyleneglycol, propylene glycol diacetate, methoxy propanediol, diethyleneglycol, acetyl acetone, cyclohexanone, propylene glycol monomethyl etheracetate, γ-butyrolactone, O-dichlorobenzene, nitromethane,tetrahydrofuran, dimethyl sulfoxide, nitrobenzene, butyl nitrite, methylcellosolve, ethyl cellosolve, diethyl ether, diethylene glycol methylether, diethylene glycol ethyl ether, dipropylene glycol methyl ether,toluene, hexane, methyl ethyl ketone, methyl isobutyl ketone,hydroxymethyl cellulose, and heptane.
 19. A method of forming a pattern,the method comprising: forming a to-be-etched layer on a substrate;forming a hardmask on the to-be-etched layer by supplying the hardmaskcomposition of claim 16, the hardmask including the 2-dimensional carbonnanostructure; forming a photoresist pattern on the hardmask; forming ahardmask pattern on the to-be-etched layer by etching the 2-dimensionalcarbon nanostructure by using the photoresist pattern as an etchingmask, the hardmask pattern including the 2-dimensional carbonnanostructure; and etching the to-be-etched layer by using the hardmaskpattern as an etching mask.
 20. The method of claim 19, wherein theto-be-etched layer includes one of a metal, a semiconductor, and aninsulator.